Allocator framework, 1st part: allocator input generation

[ganeti-local] / lib / cli.py

diff --git a/lib/cli.py b/lib/cli.py
index 8cfbeab..72e32aa 100644 (file)
--- a/lib/cli.py
+++ b/lib/cli.py
@@ -43,7 +43,7 @@ __all__ = ["DEBUG_OPT", "NOHDR_OPT", "SEP_OPT", "GenericMain", "SubmitOpCode",
            "ARGS_NONE", "ARGS_FIXED", "ARGS_ATLEAST", "ARGS_ANY", "ARGS_ONE",
            "USEUNITS_OPT", "FIELDS_OPT", "FORCE_OPT",
            "ListTags", "AddTags", "RemoveTags", "TAG_SRC_OPT",
-           "FormatError",
+           "FormatError", "SplitNodeOption"
            ]
 
 
@@ -167,7 +167,8 @@ USEUNITS_OPT = make_option("--human-readable", default=False,
                            help="Print sizes in human readable format")
 
 FIELDS_OPT = make_option("-o", "--output", dest="output", action="store",
-                         type="string", help="Select output fields",
+                         type="string", help="Comma separated list of"
+                         " output fields",
                          metavar="FIELDS")
 
 FORCE_OPT = make_option("-f", "--force", dest="force", action="store_true",
@@ -176,9 +177,13 @@ FORCE_OPT = make_option("-f", "--force", dest="force", action="store_true",
 _LOCK_OPT = make_option("--lock-retries", default=None,
                         type="int", help=SUPPRESS_HELP)
 
+_LOCK_NOAUTOCLEAN = make_option("--lock-noautoclean", default=False,
+                                action="store_true", help=SUPPRESS_HELP)
+
 TAG_SRC_OPT = make_option("--from", dest="tags_source",
                           default=None, help="File with tag names")
 
+
 def ARGS_FIXED(val):
   """Macro-like function denoting a fixed number of arguments"""
   return -val
@@ -217,7 +222,7 @@ class CliOption(Option):
 cli_option = CliOption
 
 
-def _ParseArgs(argv, commands):
+def _ParseArgs(argv, commands, aliases):
   """Parses the command line and return the function which must be
   executed together with its arguments
 
@@ -226,6 +231,7 @@ def _ParseArgs(argv, commands):
 
     commands: dictionary with special contents, see the design doc for
     cmdline handling
+    aliases: dictionary with command aliases {'alias': 'target, ...}
 
   """
   if len(argv) == 0:
@@ -239,7 +245,8 @@ def _ParseArgs(argv, commands):
     # argument. optparse.py does it the same.
     sys.exit(0)
 
-  if len(argv) < 2 or argv[1] not in commands.keys():
+  if len(argv) < 2 or not (argv[1] in commands or
+                           argv[1] in aliases):
     # let's do a nice thing
     sortedcmds = commands.keys()
     sortedcmds.sort()
@@ -261,9 +268,23 @@ def _ParseArgs(argv, commands):
         print "%-*s   %s" % (mlen, "", line)
     print
     return None, None, None
+
+  # get command, unalias it, and look it up in commands
   cmd = argv.pop(1)
+  if cmd in aliases:
+    if cmd in commands:
+      raise errors.ProgrammerError("Alias '%s' overrides an existing"
+                                   " command" % cmd)
+
+    if aliases[cmd] not in commands:
+      raise errors.ProgrammerError("Alias '%s' maps to non-existing"
+                                   " command '%s'" % (cmd, aliases[cmd]))
+
+    cmd = aliases[cmd]
+
   func, nargs, parser_opts, usage, description = commands[cmd]
   parser_opts.append(_LOCK_OPT)
+  parser_opts.append(_LOCK_NOAUTOCLEAN)
   parser = OptionParser(option_list=parser_opts,
                         description=description,
                         formatter=TitledHelpFormatter(),
@@ -286,6 +307,16 @@ def _ParseArgs(argv, commands):
   return func, options, args
 
 
+def SplitNodeOption(value):
+  """Splits the value of a --node option.
+
+  """
+  if value and ':' in value:
+    return value.split(':', 1)
+  else:
+    return (value, None)
+
+
 def AskUser(text, choices=None):
   """Ask the user a question.
 
@@ -409,7 +440,7 @@ def FormatError(err):
   return retcode, obuf.getvalue().rstrip('\n')
 
 
-def GenericMain(commands, override=None):
+def GenericMain(commands, override=None, aliases=None):
   """Generic main function for all the gnt-* commands.
 
   Arguments:
@@ -418,6 +449,7 @@ def GenericMain(commands, override=None):
     - override: if not None, we expect a dictionary with keys that will
                 override command line options; this can be used to pass
                 options from the scripts to generic functions
+    - aliases: dictionary with command aliases {'alias': 'target, ...}
 
   """
   # save the program name and the entire command line for later logging
@@ -432,7 +464,10 @@ def GenericMain(commands, override=None):
     binary = "<unknown program>"
     old_cmdline = ""
 
-  func, options, args = _ParseArgs(sys.argv, commands)
+  if aliases is None:
+    aliases = {}
+
+  func, options, args = _ParseArgs(sys.argv, commands, aliases)
   if func is None: # parse error
     return 1
 
@@ -442,11 +477,16 @@ def GenericMain(commands, override=None):
 
   logger.SetupLogging(debug=options.debug, program=binary)
 
+  utils.debug = options.debug
   try:
-    utils.Lock('cmd', max_retries=options.lock_retries, debug=options.debug)
+    utils.Lock('cmd', max_retries=options.lock_retries, debug=options.debug,
+               autoclean=not options.lock_noautoclean)
   except errors.LockError, err:
     logger.ToStderr(str(err))
     return 1
+  except KeyboardInterrupt:
+    logger.ToStderr("Aborting.")
+    return 1
 
   if old_cmdline:
     logger.Info("run with arguments '%s'" % old_cmdline)